Just saw this on youtube and it’s pretty sick. This person live streamed himself playing Tree of Savior and getting from level 1 to 325 in 12 hours.
That said, it wasn’t just a vanilla toon, which would be impossible. He already had bonuses from other maxed toons, and instant dungeon clears, exp boosts, etc.
Still, it was quite interesting to watch someone levelling so quickly in Tree of Savior with minimal grinding.